1. Field of the Invention
The present invention pertains generally to a fuel manufacturing apparatus, and more particularly to an apparatus and method for converting flammable material, such as waxed corrugated cardboard, into compact artificial firelogs or firestarter chips.
2. Description of the Background Art
The popularity of log burning fireplaces as an amenity and as a supplemental source of heat continues to grow. With cutting restrictions on Government land, as well as the closing of many wood processing plants, wood logs can be difficult and expensive to obtain. As a result, artificial firelogs, which generally burn cleaner and light faster, have been gaining in popularity.
On the other hand, boxes and containers made from cardboard are widely used in an almost infinite variety of applications such as packaging produce, shipping and storage of goods and the like. As such, there is an abundant supply of discarded cardboard boxes readily available for recycling. It has been recognized that discarded cardboard boxes form a potential fuel material, and the general concept of converting used or discarded cardboard boxes into burnable firelogs has been applied with some level of success.
Machines have been previously developed to convert such cardboard boxes into compact burnable firelogs. Such machines include a feed system, such as a hammermill for receiving a sheet of cardboard, a cutting mechanism for slicing the cardboard sheet into strips and then cutting the strips into chips, and a compacting/compressing punch press assembly for shaping the chips into compact firelog structures which can be burned in a fireplace. Binders, such as glue, are used to hold the chips together after compression. Additionally, the finished firelogs can be dipped into wax to create an outer wax coating to enhance their burn capability.
These existing machines, however, are designed to cut and shape plain cardboard boxes; that is, cardboard without a wax or wax-like coating thereon. Existing machines are not made to cut and shape waxed corrugated cardboard. Furthermore, the design of these machines does not take into account that, by using glue as a binder to hold regular unwaxed cardboard together into a compressed log, the corrugations are destroyed when the strips or chips are smashed and glued together. Quite significantly, we have found that regular and waxed corrugated cardboard has a memory and, while the corrugated segments stick together they are flattened and compressed, if glue is not used as a binder, upon heating the corrugated segments expand back into an open structure through which airflow is increased which leads to more efficient burning. Current fire log production machines are not able to make use of this memory property of corrugated cardboard.
It will be appreciated that resource conservation continues to be important as our population increases and our level of resources diminish. Therefore corrugated cardboard boxes, as is the case with many other materials, are generally recycled to reduce waste. Wax-coated corrugated cardboard boxes, however, are generally non-recyclable. Wax-coated corrugated cardboard boxes are commonly coated with a paraffin-based wax which is very expensive to separate from the cardboard within a normal re-pulping systems. Consequently, used wax-coated corrugated cardboard boxes (WOCC) are generally discarded in landfills. In view of present interests regarding conservation of resources and environmental consciousness, the ability to reuse such discarded material in a form of fuel would serve to reduce the demand for other types of fuels, such as oil, gas or coal, thus further conserving natural resources and preserving the environment.
Additionally, current log manufacturing machines destroy the corrugation within the corrugated cardboard which reduces the flow and permeation of wax and oxygen throughout the firelog which results in an incomplete and inefficient burning of the firelog.
Moreover, current log manufacturing machines produce firelogs with “cold joints” at the intervals between punches or presses. These cold joints are also formed when the chips are compressed vertically within the structure of the log rather than disposed horizontally around the log in a circular fashion. Cold joints are weak links within the firelog that easily break up into multiple sections when any shear or tensile force is exerted upon them. The punch or press machine creates vertical arrangements of the chips within the firelog. When burned, the vertical chip arrangement causes chips to burn from the edge rather than from the side. Therefore chips of corrugated cardboard, so pressed into a log, are not allowed to open and expand with heat because of the vertical arrangement and the glued corrugations.
Accordingly, there exists a need for an artificial firelog manufacturing apparatus that provides the capability to recycle pre-waxed corrugated cardboard boxes into firelogs that are more structurally rigid and that burn more efficiently, using horizontally disposed segments, over that which is presently known in the art. The present invention satisfies those needs, as well as others, and overcomes the deficiencies found in currently known artificial firelog producing machines.